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41.
Manfredo Hörner Gelson Manzoni de Oliveira Eduardo Giuliani Koehler Lorenzo do CantoVisentin 《Journal of organometallic chemistry》2006,691(6):1311-1314
Deprotonated 1,3-bis(3-acetylphenyl)triazene reacts with Hg(CH3COO)2 and pyridine to give light-yellow crystals of {[HgII(RC6H4NNNC6H4R)2Py]}n (R = acetyl). The tectons [HgII(RC6H4NNNC6H4R)2Py] [R = CH3C(O)] are linked to pairs as centrosymmetric dimers through reciprocal metal-η2-arene π-interactions. The dimeric units are operated by a screw axis 21 parallel to the crystallographic direction [0 1 0], also through a reflection-translation plane parallel to the c-axis, resulting a supramolecular bidimensional (2D) assembling of the dimeric tectons through non classical C-H?(O)CCH3 bonding. 相似文献
42.
1INTRODUCTION The construction of metal-organic coordination polymers based on covalent interactions[1]or supra-molecular contacts such as hydrogen-bonding and/orπ-πinteractions)[2]is now of great interest not only due to the enormous variety of intriguing structural topologies themselves,but also to their unexpected physical and chemical properties for potential prac-tical applications as functional materials.Many N-containing ligands,such as4,4?-bipyridine,2,2?-bi-pyridine and1,10-phen… 相似文献
43.
Stereoselective route to tricyclo[5.3.1.01,5]undecane and bicyclo[4.2.0]octane ring systems present in the molecular structure of tricycloillicinone, cedrenoids and endiandric acid, elysiapyrones, respectively, is described. A tandem oxidative dearomatization of o-hydroxymethylphenol, π4s+π2s cycloaddition, reactivity modulation in excited state and ring-closing metathesis are the key features of our approach. 相似文献
44.
A series of formyl-substituted 5-aryl-2,2′-bithiophenes 5 were synthesized using two different methods: Vilsmeier-Haack-Arnold reaction (VHA) or through Suzuki coupling. The synthesis of compounds 5 through the Vilsmeier-Haack-Arnold reaction, starting from inexpensive and easily available precursors such as acetophenones, gave the title compounds in low yields after four reaction steps. On the other hand Suzuki coupling of functionalized arylboronic acids 7 and the 5-bromo-5′-formyl-2,2′-bithiophene 6 gave compounds 5 in good yields in only one step. 相似文献
45.
Alexander Jakob 《Journal of organometallic chemistry》2008,693(23):3479-3489
2,2′-Bipyrimidine metal complexes with Ti, Mo, Fe, Ru, Pt, Ag, and Cu transition metal atoms have been synthesized and structurally characterized. These molecules were prepared by following synthesis methodologies. The reaction of 2,2′-bipyrimidine (1; bipym) with {[Ti](μ-σ,π-CCSiMe3)2}AgOTf ([Ti] = (η5-C5H4SiMe3)2Ti, OTf = OSO2CF3) (2) in a 1:1 molar ratio gave [{[Ti](μ-σ,π-CCSiMe3)2}Ag(bipym)]OTf (3) which on further treatment with another equivalent of 2 produced [({[Ti](μ-σ,π-CCSiMe3)2}Ag)2(μ-1,2,3,4-bipym)](OTf)2 (4). As consequence thereof, the coordination number of Ag(I) was changed from 3 to 4. A platinum-bipym complex with two acetylide substituents was accessible by the gradual reaction of 1 with K2[PtCl4] (5) and two equivalents of HCCR (7a, R = SiMe3; 7b, R = Fc; 7c, R = Rc; Fc = (η5-C5H4)(η5-C5H5)Fe; Rc = (η5-C5H4)(η5-C5H5)Ru) in di-iso-propylamine and in presence of [CuI]. Originating from cis-[(bipym)Pt(CCR)2] (8a, R = SiMe3; 8b, R = Fc; 8c, R = Rc) diverse multinuclear complexes with two, three or four different transition metals could be obtained. These are: [((CO)4Mo)(μ-1,2,3,4-bipym)Pt(CCFc)2] (10), [(AgClO4)(μ-1,2,3,4-bipym){[Pt(μ-σ,π-CCFc)2]AgOClO3}] (12), [(McCC)2Pt(μ-1,2,3,4-bipym)({[Ti](μ-σ,π-CCSiMe3)2}M)]X (15a, Mc = Fc, M = Cu, X = PF6; 15b, Mc = Rc, M = Cu, X = PF6; 15c, Mc = Fc, M = Ag, X = ClO4), and [(McCC)2Pt(μ-1,2,3,4-bipym)PtCl2] (17). Like other organometallic Pt-Ag tweezer complexes, compound 12 decomposed to give FcCC-CCFc (13). During prolonged stirring of 15a and 15b, respectively, [(McCC)2Pt(μ-1,2,3,4-bipym)({[Ti](μ-σ,π-CCSiMe3)(μ-σ,π-CCH)}M)]X (15′a, M = Cu, X = PF6; 15′b, M = Cu, X = PF6) was formed.The structures of 8b, 8c, 15a′, and 15b′ in the solid state are reported. All complexes exhibit the anticipated planar dinuclear Pt-M structure (M = Pt, Cu, Ag) with the 2,2′-bipyrimidine unit in a μ-1,2,3,4-bridging mode.Electrochemical investigations were carried out with 8a, 8b, and 8c and show that no significant influence of R on the bipym redox potentials exists. The typical redox behavior for the bipym, ferrocene, ruthenocene units and platinum were observed. 相似文献
46.
LI Yana b WU A-Qinga b ZHENG Fa-Kuna② GUO Guo-Conga② LU Can-Zhonga HUANG Jin-Shuna a 《结构化学》2005,(11)
1 INTRODUCTION Exploration on the syntheses and properties of car- boxylate complexes, especially aromatic carboxylate complexes, has always been a fascinating and chal- lenging research field for decades either in coor- dination chemistry or in functional materials[1, 2]. Cy- anobenzoic acid (Hcba) possessing two functional coordination groups should display structural diver- sities on the formation of complexes[3~15]. In particu- lar, the copper(II) carboxylate complexes bearing spe- … 相似文献
47.
48.
Three new lacunar-type derivatives of β-unsubstituted dibenzotetraaza[14]annulene have been synthesized along with a range of their open-chain pendant group containing counterparts. The crystal structures of two representative products have been determined and the noncovalent interactions explored. A number of C-H?π and π?π interactions involving aliphatic chains and aromatic regions of the macrocycle have been evidenced. The relative ease and high yield of lacunization are suggested to be largely due to self-assembly processes, driven by favorable noncovalent interactions between reacting units. 相似文献
49.
Myung-Seok Choi 《Tetrahedron letters》2008,49(49):7050-7053
A series of new porphyrin derivatives possessing the side arms of alkyl-substituted thiophene oligomer were synthesized. The effects of solvent polarity on the formation of supramolecular assembly have been studied by UV-vis absorption, fluorescence emission, and TEM measurement. The linear-shape porphyrin derivatives bearing two thiophene pentamers at meso-position showed the significant spectral changes in both blue-shift and band broadening of Soret bands which indicate the formation of a relatively larger porphyrin H-aggregate that occurred in nonpolar solvent such as n-hexane. 相似文献
50.
We described the design and synthesis of a colorimetric and ratiometric fluorescent probe based on a conjugated π-electron system that displayed differential fluorescence responses towards cyanide and sulfide and demonstrated its utility in intracellular ion imaging and logic gate. 相似文献